1. Field of Invention
This invention relates generally to conveyor systems principally used in the mining and material handling industry. More particularly, the invention relates to the design of conveyor impact beds often used to support a conveyor belt in a loading zone, where soil, rocks, gravel and other aggregate material drops onto a conveyor belt.
2. Description of Related Art
Conveyor belts are used in a variety of industries to transport materials from one place to another. Generally, materials are deposited at one end of a conveyor and are transported to the other end, where they are discharged or otherwise removed from the conveyor belt. The belts used are often robust, but are susceptible to damage from a variety of sources. While discharge of materials from a conveyor belt does not usually damage the belt, the act of depositing goods and materials onto a conveyor belt has the potential to cause damage. In this regard, when a belt is being used to transport coal, aggregate and other coarse and heavy material, the deposit of these types of materials onto the belt can generate tremendous impact forces on the belt. For instance, with a 100 lb mass having drop distance of 10 feet from a discharge chute onto a conveyor belt, there is 1,000 ft-pounds of force impacting the belt.
It is standard in the industry to provide an impact bed to support and protect the conveyor belt in the loading zone. An impact bed is an apparatus which is installed below the area of the conveyor belt on which heavy loads are deposited, and absorbs the impact forces generated thereby, as discussed above. Typical impact beds include a plurality of support members longitudinally spaced from each other under the area of the belt in the loading zone. These support members have a plurality of resilient impact bars secured thereto, which extend thereacross running lengthwise in the belt travel direction. The bars absorb the impact forces and decrease the acceleration of the materials or rocks dropped onto the belt.
The support members and impact bars supported thereby typically provide a trough configuration for the belt. This prevents aggregate materials from spilling over the edges of the belt as such materials are discharged onto, and transported along the belt. The support members typically include a planar portion, which supports the impact bar(s) in a flat configuration, and inclined angled wings on both sides of the planar portion. Each inclined angled wing supports the impact bar(s) at a troughing angle relative to the planar portion.
The resilient bars are subject to wear and damage over repeated impacts with the belt and thus need to be serviced and/or replaced on a regular basis. In addition, the belt tends to experience significant wear and damage, particularly at the belt junction between impact bars supported by the planar portion and impact bars supported by the angled wing portion. Accordingly, there exists a need for a means to minimize damage at the belt junction of impact beds.